This invention is directed to a method and apparatus for removing byproducts, such as ammonia and hydrogen sulfide, from waste water streams produced by chemical processing plants, such as oil refineries or coking operations.
Aqueous waste water streams produced in the oil refining industry generally include nitrogen and sulfur contaminants. The waste water streams typically contain about 1 to 3% ammonia, and an equivalent or greater concentration of acid gas (i.e., hydrogen sulfide). Many oil refineries treat this aqueous waste water by steam stripping the waste water, producing a vapor stream containing water, ammonia and hydrogen sulfide, and feeding this vapor to a sulfur recovery unit (SRU).
There is a need for a method for more efficient removal and processing of byproducts from waste water streams. There is also a need for a method for removal and processing of byproducts using economies of scale, allowing for processing of the byproduct material(s) from one or more plants at a remote facility.